In September 2016, the Coroner’s Court of Queensland delivered its findings into the death of Michael Calder. Mr Calder died from opiate toxicity during an admission to hospital for investigation and treatment of a severe headache.


On 8 July 2014, Michael Calder, 33, was referred to the Holy Spirit Northside Private Hospital by his general practitioner after presenting with a three day history of severe occipital headaches, neck pain and stiffness.

Mr Calder was given analgesia, including IV morphine, in the Emergency Department before being admitted to the ward under the care of a specialist general physician.

During the course of his ward admission, Mr Calder received analgesia for the ongoing headache, including subcutaneous morphine, oxycodone, Ordine (liquid morphine), MS Contin (slow release morphine), Gabapentin (neuropathic pain) along with paracetamol and ibuprofen.

The prescribed medication was administered at regular intervals between the admission and the time of Mr Calder’s sudden and unexpected death at 5:17am on 11 July 2014.

In the days leading up to his untimely death, the treating doctors and nurses recalled Mr Calder to be coherent, not slurring his words and on occasion, moving around the room when awake. He had also been noted to be snoring heavily when sleeping, including on the night of 10 July until the early hours of the following morning when he was only snoring softly, likely due to heavy sedation by narcotics depressing his respiratory drive.

Formal recording of Mr Calder’s oxygen saturations did not occur on every ward round, though the recorded observations did indicate that his oxygen saturations had fallen to less than desirable levels, requiring oxygen administration through nasal prongs.

During the morning of 10 July, Mr Calder’s oxygen saturations were recorded at 91% at 4:00am and 88% at 8:00am, necessitating supplemental oxygen. At 11:30am, his oxygen saturations were 93% and at midnight 90%.

The Coroner found that there was nothing in the notes to indicate that the treating physician noticed these periods of hypoxaemia, nor the requirement for oxygen supplementation, nor any indication of what might be the possible cause.

When an Endorsed Enrolled Nurse (EEN) entered Mr Calder’s room at 4:40am on 11 July to check on him and to take his observations, there was no snoring and she thought he looked different. The EEN put a light on and noticed he looked pale. A Code Blue was called and CPR commenced. Mr Calder could not be resuscitated and was pronounced dead at 5:17am.

Expert evidence provided to the Coroner supported a finding that:

• Mr Calder’s oxygen saturation levels on 10 July were consistent with excessive sedation causing worsening obstructive sleep apnoea or aspiration.

• The combination of large doses of narcotics and episodes of intermittent hypoxaemia should have alerted the clinicians that Mr Calder required very close observation, ideally not in a single room with the door closed, and that these concerns should have been clearly articulated to the nursing staff looking after Mr Calder overnight.

• The factors that are likely to have resulted in Mr Calder’s deterioration were a combination of sleep apnoea (a pre-existing condition that hospital staff failed to record upon admission) and the combination of the slow release OxyContin, oral Ordine (morphine) and gabapentin.


The Coroner found that a combination of poor communication, poor documentation and a lack of safeguards resulted in a number of missed opportunities to diagnose the deterioration in Mr Calder’s condition1 .

Mr Calder’s death emphasised the importance of systems being in place to recognise and manage a deteriorating patient through tools, such as Standard 9 of The National Safety and Quality Health Service Standards, which contains a specific component for recognising and responding to clinical deterioration, as well as the importance of systems being in place to promote the dissemination of accurate and relevant information at clinical handovers.

The Coroner found that there was certainly evidence of reduced oxygen saturations throughout Mr Calder’s admission. Unfortunately, however, there were a number of occasions when nurses did not record his pain scores, oxygen saturation levels, or actions taken in response. This meant staff did not have a clear picture of the progression of his pain and oxygen saturation levels and missed critical opportunities to intervene and halt his continued deterioration.

The Coroner noted the efforts by the hospital to implement improvements to address the issues identified. For that reason, the Coroner did not make any further recommendations to be implemented by the hospital.


The finding demonstrates the critical importance of adequate communication, up to date record keeping and well known and followed policies and procedures.

Mr Calder’s widow has issued proceedings against the hospital in the Queensland Supreme Court.